Ay, normal lang talaga na mag-ubo ang newborn lalo na pag may slight irritation sa throat o nakaposisyon lang siya ng weird, kaya wag mag-alala kung occasional lang! But since siya's still so tiny at just about a month old, I'd really suggest checking in with your pedia just to be sure, one of my mum friends had a baby na umuubo and turned out it was just milk going down the wrong way, but mas okay na verified ng doctor para sa peace of mind mo.